Continuity mistake: When Sid tells Joan that they are not staying at the Paradise Camp, Joan says "What?" and you can see outside her window that the car is next to a bush. When we see Sid getting out of the car in the next shot, the bush is nowhere to be seen.
Continuity mistake: When Dr. Soaper asks the girls if they have any questions regarding Stonehenge on the coach, two girls stand up behind Babs and Fanny, but in the next shot when Fanny says "Go on, Babs, I dare you!", they are sitting down again.
Continuity mistake: During the scene when Sid James is tying up the necklaces of the hippies at the rave-up, one of them he ties up is a blonde haired man with a striped shirt and brown jacket. But when we see "The Flowerbuds" performing a little later on, this man is no longer tied up - he is now dancing with the other hippies.